In isosceles triangle R S T, \angle S R T is 70 degrees. Find m \angle R S T.
Choices:
A:55
B:70
C:75
D:80
Please directly answer the question and provide the correct option letter, e.g., A, B, C, D.
Question: In isosceles triangle R S T, \angle S R T is 70 degrees. Find m \angle R S T.
Choices:
A:55
B:70
C:75
D:80
Please first conduct reasoning, and then answer the question and provide the correct option letter, e.g., A, B, C, D, at the end.
Question: In isosceles triangle R S T, \angle S R T is 70 degrees. Find m \angle R S T.
Choices:
A:55
B:70
C:75
D:80