Answer: 4.0 (choice C)
Reason
"ceil" refers to "ceiling". The ceiling function rounds up to the nearest whole number. The value 3.6 naturally rounds to 4 without needing a ceiling function.
Something like 3.1 and 3.01 and 3.001 will all round to 4 when applying the ceiling function. It doesn't matter how close they are to 3; we always round up.