Creative persistence is often useful when one is designing an experimental paradigm for example. It is useful tweaking different parameters of an idea which is much easier when one is creative - this is also at the core of scientific research very often.
I think marine, but I’m not so sure
The answer is A. Sex-linked traits are more often expressed in males because they are typically carried by the X chromosome and they are also typically recessive. Males only inherit one X chromosome, so if the one they inherit is linked to the disease, they will express it no matter what. Females, on the other hand, can be carriers if they inherit one X chromosome with the disease. This is because their other X chromosome can be normal, which would dominate the expression of the disease on their other X chromosome.