The correct answer is pollution.
Genotype heterozygous tells you the alleles are different, which is found in the genotype
The correct order is:
B. Rain water is stored in rock and seeps into a hairline crack during a rainfall;
E. The temperature falls below 0° Celsius;
D. Rainwater in the rock crack freezes into ice;
C. Because ice occupies more space than water, the ice wedges the crack open:
A. The freeze-thaw cycle continues to deepen the crack until the rock splits into 2 pieces;
The water from the rain gradually manages to weather parts of the rock. As it does, small cracks appear in it. Once there's cracks, the water from the rainfall also starts to store inside the rock. When the colder period of the year comes, and the temperatures fall bellow 0°C, the stored water freezes. The ice starts to spread inside the crack, thus creating pressure inside the rock. As the pressure is becoming bigger and bigger, the rock will eventually crack into two or more pieces.
