TASK DEFINITION: Given scientific fact as input, generate the question from this fact such that it can be answered from the input.
PROBLEM: Three many families are known quarks divided into.

SOLUTION: How many families are known quarks divided into?

PROBLEM: Activities that can reduce the effects of edema condition include exercises to keep the blood and lymph flowing through affected areas.

SOLUTION: Activities that can reduce the effects of what condition include exercises to keep the blood and lymph flowing through affected areas?

PROBLEM: We all start as a single cell and soon grow into a(n) embryo.

SOLUTION:
We all start as a single cell and soon grow into what?