TASK DEFINITION: Given scientific fact as input, generate the question from this fact such that it can be answered from the input.
PROBLEM: Gabbro is a dark dense rock that can be found in the oceanic crust.

SOLUTION: Gabbro is a dark dense rock that can be found in what?

PROBLEM: A(n) an ionic bond forms when the metal sodium gives up an electron to the nonmetal chlorine.

SOLUTION: What forms when the metal sodium gives up an electron to the nonmetal chlorine?

PROBLEM: Some species of fish carry their fertilized eggs in their mouth until they hatch; this is called mouth brooding.

SOLUTION:
Some species of fish carry their fertilized eggs in their mouth until they hatch; this is called what?