Explanation:

- The average age of 7 family members is 40 years, so total age = 7 × 40 = 280 years.

- The three men have an average age of 48, so their total age = 3 × 48 = 144 years.

- The three women have an average age of 44, so their total age = 3 × 44 = 132 years.

- Adding men and women: 144 + 132 = 276 years.

- The only one left is the boy: Boy's age = 280 – 276 = 4 years.

Option 1: 6 years ?

Option 2: 2 years ?

Option 3: 4 years

Option 4: 8 years ?