Calculate quantity index for the year 2015 with 2013 as base:

105.71

The correct answer is Option (2) → 105.71

Quantity Index = $Q_{01}=\frac{​∑Q_1}{∑Q_0} ​​×100$

where
$Q_0$​ = quantities in base year (2013)
$Q_1$​ = quantities in current year (2015)

$Q_{01} = \frac{\sum Q_1}{\sum Q_0} \times 100 = \frac{296}{280} \times 100 = 105.71 \text{}$