System, method, and computer program product for performing an operation, the operation comprising receiving, by a deep question answering system, a question not specifying an element of input data, identifying a set of possible values for the element of input data, generating, by the deep question answering system, a respective set of candidate answers for the question: (i) without the element of input data, and (ii) with each possible value in the set of possible values for the element of input data, and returning at least one candidate answer from at least one set of candidate answers as responsive to the question.
Please help me write a proper abstract based on the patent claims. CLAIM: 1-9. (canceled) 10. A computer program product, comprising: a computer-readable storage medium having computer-readable program code embodied therewith, the computer-readable program code comprising: computer-readable program code configured receive, by a deep question answering system, a question not specifying an element of input data; computer-readable program code configured identify a set of possible values for the element of input data; computer-readable program code configured to generate, by the deep question answering system, a respective set of candidate answers for the question: (i) without the element of input data, and (ii) with each possible value in the set of possible values for the element of input data; and computer-readable program code configured to return at least one candidate answer from at least one set of candidate answers as responsive to the question. 11. The computer program product of claim 10, wherein the set of possible values for the element of input data are identified in a corpus of information as being relevant to the question. 12. The computer program product of claim 10, wherein the element of input data comprises a set of distinct input data elements, wherein candidate answers are generated for each possible value in a set of possible values for each distinct input data element in each set of distinct input data elements. 13. The computer program product of claim 10, further comprising: computer-readable program code configured to, prior to generating the respective sets of candidate answers, determine that a count of the possible values in the set of possible values does not exceed a maximum threshold. 14. The computer program product of claim 10, further comprising: computer-readable program code configured to determine that at least one possible value, of the set of possible values for the element of input data, allows the deep question answering system to identify an item of supporting evidence that is not identified when the element of input data is not included in the question. 15. The computer program product of claim 10, further comprising: computer-readable program code configured to determine that at least one possible value, of the set of possible values for the element of input that the element of input data, when not included in the question, impacts a confidence score of at least one candidate answer, of the set of candidate answers for the question without the element of input data, beyond a specified confidence threshold. 16. The computer program product of claim 10, further comprising: computer-readable program code configured to, subsequent to returning the at least one candidate answer, provide an interface configured to receive, from a user, a value for the element of input data. 17. The computer program product of claim 10, further comprising: computer-readable program code configured to determine that a first candidate answer included in each respective set of candidate answers generated for the question with each possible value in the set of possible values for the element of input data, has a confidence score greater than a confidence score for all other candidate answers in each respective set of candidate answers; and computer-readable program code configured to return the first candidate answer as responsive to the question. 18. The computer program product of claim 1, wherein a subset of the candidate answers of a subset of the respective sets of candidate answers are returned as responsive to the question. 19. A system, comprising: one or more computer processors; and a memory containing a program, which, when executed by the one or more computer processors, performs an operation comprising: receiving, by a deep question answering system, a question not specifying an element of input data; identifying a set of possible values for the element of input data; generating, by the deep question answering system, a respective set of candidate answers for the question: (i) without the element of input data, and (ii) with each possible value in the set of possible values for the element of input data; and returning at least one candidate answer from at least one set of candidate answers as responsive to the question. 20. The system of claim 19, wherein the set of possible values for the element of input data are identified in a corpus of information as being relevant to the question, wherein the element of input data comprises a set of distinct input data elements, wherein candidate answers are generated for each possible value in a set of possible values for each distinct input data element in each set of distinct input data elements.