Varicose veins seen in the superficial veins of the legs are unsightly and are often treated by surgical removal. However, even without these veins being present, the return of all blood toward the heart from the legs is not diminished. This is primarily because .

hi~~

i would say that hybridization occurs frequently in nature, because there are many types of hybrids that have occurred naturally, such as the mule (male donkey + female horse)

looks like the answer is     c     to me!

the answer is 100% density i've answered this question before and done the quiz myself.