Answer:
Let's complete the question by writing the sequence, from earliest to most recent options
a. 2 → 1 → 3 → 4
b. 2 → 4 → 3 → 1
c. 2 → 3 → 1 → 4
d. 2 → 1 → 4 → 3
e. 2 → 4 → 1 → 3
It's surely going to be e.
e. 2 → 4 → 1 → 3
2. Cambrian explosion occurs.
4. Vertebrates become top predators in the seas.
1. Protostomes invade terrestrial environments.
3. Deuterostomes invade terrestrial environments.
Got it!
Lead to more test and what you think about whatever your conclusion is about
I’m not sure what your asking. But if you have 2 different alleles of a gene it will be heterozygous