Given a list of steps and an additional step, determine where the step fits into the original list of steps. A correct answer, correctly places the given step into the set of steps so that it creates a new plausible set of steps. Output must be formatted as 'After step n', where n is the step number after which the given additional step is to be inserted.
One example is below.
Q: Steps: (1) Solar radiation reaches Earth's atmosphere (2) Some is reflected back into space (3) The rest of the energy is absorbed by land and oceans, heating the Earth (4) Some of this heat is trapped by greenhouse gases in the atmosphere (5) Human activities such as burning fuel are increasing the amount of greenhouses gases (6) This causes more heat radiation to stay trapped in our atmosphere (7) The Earth's temperature rises  
Where does the following step fit into the given list of steps: Heat radiates from Earth to space 
A:  After step 3. 
Rationale: The correct answer is 'After step 3'. The given step is 'Heat radiates from Earth to Space'. Step 3 introduces a new concept of generated heat. Step 4 mentions that the heat is trapped into the atmosphere. In order for the heat to get to the atmosphere, the heat must radiate from Earth to space. Therefore, the correct answer is 'After step 3.'
Q: Steps: (1) A virus enters a host body (2) The virus has receptors that lock onto a target cell (3) The virus uses the cell like a factory to make new copies of the virus (4) The new copies of the virus leave the cell (5) Infect other cells (6) The host gets sick as its cells are damaged.  
Where does the following step fit into the given list of steps: The virus enters the cell 
A:
 After step 2. 