A) Someone who has broken their leg.
This is because they will most likely be more sedentary.
Also by process of elimination.
Can't be B because why would someone who is jogging/exercising need to reduce calorie intake? If anything they'd want to increase it to make up for what they're losing.
Can't be C because someone who is pregnant should increase their calorie intake because they're feeding an extra (or in this case two extra) people.
Can't be D because again, this person is excersising, which means more calories out, which means a greater need for calories in.
Final answer A) "someone who has broken a leg"