In this task, you're given four sentences of a story written in natural language. The given story is not complete and your job is to complete the story by selecting one of the sentence choices from (A) and (B), such that the story sounds fully coherent.
One example: Sentence1: Rick grew up in a troubled household. Sentence2: He never found good support in family, and turned to gangs. Sentence3: It wasn't long before Rick got shot in a robbery. Sentence4: The incident caused him to turn a new leaf. 
 (A) He is happy now. (B) He joined a gang.
Solution is here: A
Explanation: As mentioned in fourth sentence, the incident turned a new leaf to Rick's life; so, he must be happy now.

Now, solve this: Sentence1: Dan wanted to find the perfect gift for his mother's birthday. Sentence2: He shopped at the mall for hours and was unable to find anything. Sentence3: He came home disappointed and without a gift. Sentence4: His mother saw his face when he walked in and asked what was wrong. 
 (A) Dan explained the situation and his mother was not upset. (B) Dan yelled at his mom for being picky.
Solution:
A