You will be given a definition of a task first, then some input of the task.
In this task, you are given two facts, and a multiple-choice question. Based on the given facts, answer the question with index of the correct option (e.g, "A").

Fact1: a graduated cylinder is used to measure volume of a liquid, Fact2: For test cylinders without graduation marks, a manual calibration method has to be used., Question: graduation markings are used to measure the what of a liquid (A) viscocity (B) size (C) flow (D) volume (E) density (F) smell (G) Decibels (H) tube
Output:
D