Tail-Feather Length in Birds Is Sometimes a Sexually Dimorphic Trait

Tail-feather length in birds is sometimes a sexually dimorphic trait. That is, the trait differs substantially for males and for females. Researchers studied the relationship between tail-feather length (measuring the R1 central tail feather) and weight in a sample of 20 male long-tailed finches raised in an aviary. The data are represented in the following scatterplot, along with the least-squares regression line equation and the square of the correlation coefficient (R²) .
What is the value of the slope for the male regression line?

A) 2.8299 g/mm
B) 2.8299 mm/g
C) 35.738 mm/g
D) 35.738 g/mm