what is the dBi value?

If an antenna has a dBd of 8.6, what is the dBi value?

A.
6.2

B.
6.46

C.
8.6

D.
10.74

E.
12.88

Explanation:
Antenna performance
Antenna performance is measured in
dBi (the antennas gain/loss over a theoretical isotropic antenna)
dBd (the antennas gain/loss over a dipole antenna)
dBi = dBd + 2.15
dBd = dBi – 2.15