Answer:
b. +3 and +6.
Step-by-step explanation:
Zeff = Z - S
The Z denotes the no of protons i.e. atomic number
S denotes the non-valence electrons
For boron,
the electronic configuration is 1s₂ 2s₂ 2p₄
Now
Z = 5, S = 2
So,
Zeff = 5-2
= +3
For O, the electronic configuration is 1s₂ 2s₂ 2p₄
So,
Z = 8, S = 2
= 8-2
= +6
Hence, the second option is correct