Hello from MrBillDoesMath!
Answer:
Choice E.
Discussion:
Assuming that n >=1, a(n) = 4n -1, then
a(10) = 4(10) - 1 = 39
but that doesn't match any of the answers...... hmm...
BUT
If you meant that a(n) = 4^(n-1), then
a(10) = 4^(10-1) = 4^9 = 262144
which is Choice E.
Thank you,
MrB