Which relationship most likely reflects both correlation and causation?

Question

a. Making milkshakes more often is associated with buying ice cream more often
b. Making milkshakes more often is associated with wearing sunglasses more often
c. Making milkshakes more often is associated with making smoothies more often
d. Making milkshakes more often is associated with going to the pool more often

Answer 1

d. Making milkshakes more often is associated with going to the pool more often