The correct answer is B. 3,000 units.
The breakeven point is the number of units that must be sold in order to cover all costs. In this case, the fixed costs are Rs. 30,000 per annum, the variable cost per unit is Rs. 5, and the selling price per unit is Rs. 15. Therefore, the breakeven point in units is:
Breakeven point = Fixed costs / (Selling price per unit – Variable cost per unit)
= 30,000 / (15 – 5)
= 30,000 / 10
= 3,000 units
The other options are incorrect because they do not represent the breakeven point. Option A is incorrect because it is less than the variable cost per unit. Option C is incorrect because it is more than the fixed costs. Option D is incorrect because it is more than the annual sales demand.