People speculate when they consider a situation and assume something to be true based on inconclusive evidence. Which situation below is the best example of Speculation ?

A. Francine decides that it would be appropriate to wear jeans to her new office on Friday
after reading about "Casual Fridays" in her employee handbook.
B. Mary spends thirty minutes sitting in traffic and wishes that she took the train instead of
driving.
C. After consulting several guidebooks and her travel agent, Jennifer feels confident that the
hotel she has chosen is first-rate.
D. When Emily opens the door in tears, Theo guesses that she's had a death in her family