To determine which assumptions are implicit in the statement, we must analyze the logical relationship presented.
The statement suggests that during economic hardships, adopting education and a small family norm may benefit the nation by promoting progress and prosperity.
Assumption A: "Education and small family norms are directly related to nation’s progress."
This is implicit. The statement directly correlates education and small family norms with national progress, suggesting that these are factors contributing to prosperity during economic hardships.
Assumption B: "Big families find it difficult to bear the cost of education."
This is not implicit. While the statement discusses small family norms, it does not explicitly make any claim or assumption about the financial burdens of big families regarding education.
Given these analyses, the correct option is: Only A is implicit.