what's the problem??
if you tell, I can give some advice
Answer:
stop asking just do it bro
Explanation:
D. Having to miss an outing with friends because you are injured.
Part of the placenta (first blank)
The embryo (Second blank)
I'm can't give much of an explanation as to why so sorry about that but the answer to your question would be A, as the principle of uniformitarianism is about geological processes acting the same in the past as they did now.