Minerals all have a
structure with the same
composition

Minerals all have a solid chemical compound that occurs naturally in pure form.

i got something better   a catchphrase here it is

ahem  

ahem

what the squwock

explanation:

c) 50% there are four chromosomes. after crossing over, 2 of the four have been changed. that means any gamete has a 2 in 4 chance or 50% chance of receiving the mutated chromosome.