It is B, you are finding the infinitive as a direct object, in the answer B "to drink water" is the infinitive.
The answer is to identify the supporting details.
Answer: The children’s host in Chesham still cared about them after they left.
Explanation:
The passage is derived from the "Children of the Wartime Evacuation” and refers to a story about siblings, Sheila Shear and her sister who were evacuated during the Second World War to Cheshem and placed in the care of Harry Mayo.
Even though he was Christian and they were Jewish, he cared for them so deeply that they kept visiting after the war and Sheila and her mother even attended his funeral.
Perhaps the most evidence of his care was by his own admission when, after his death, his lawyer sent the siblings a cheque with a note saying, "A very small token of my very GREAT AFFECTION."
