Answer: Fourth option is correct.
Step-by-step explanation:
Since we have given that
Number of light bulbs = 10
Probability of defective bulbs = 5% = 0.05
Probability of non defective bulbs = 1-0.05 = 0.95
So, using "Binomial distribution", we get that :
[tex]Mean=np=10\times 0.05=0.5\\\\Variance=np(1-p)=npq=10\times 0.05\times 0.95=0.475[/tex]
Hence, Fourth option is correct.