The sequence would be written as:
1.2, 0.84, 0.588, 0.4116
If this is a geometric sequence, then they should have a common ratio. We determine as follows:
0.4116 / 0.588 = 0.7
0.588 / 0.84 = 0.7
0.84 / 1.2 = 0.7
r = 0.7
an = a1(r^(n-1))
an = 1.2 (0.7^(5-1))
an = 0.28812 <--------option A