The word "pour" is a verb that means to make a liquid flow from one container to another, or to describe something flowing in a steady stream.
A: Correct usage - "Pour" is used to describe pouring water, which is the literal and common use of the word.
B: Correct usage - "Pour" is used metaphorically to describe tears flowing, which is an accepted and natural expression.
C: Correct usage - Though slightly figurative, "pour their ideas" is a common idiom meaning to express or share thoughts freely. It fits casual or expressive language.
Thus, option (d) is the correct answer.