After he interrogated the suspect, suspicion began to Germinate into the inspecter's mind.
The answer is B. because this is the only answer that is an immediate call to action for the situation, instead of just telling you facts like the other answers, this answer tells you straight up what you should do.
The answer is B) because the subject of a sentence is a person place or thing or a idea you can find the subject of a sentence once you find the verb Hope This Helps:)