If direct material cost is $85000 and direct manufacturing labour is $25000, then prime cost would be

$13,500
$55,600
$60,000
$110,000

The correct answer is $\boxed{\text{C}}$.

Prime cost is the direct costs attributable to the production of a product. It is calculated by adding direct material cost and direct labor cost.

In this case, direct material cost is $85,000 and direct labor cost is $25,000. Therefore, prime cost is $85,000 + $25,000 = $110,000.

Option A is incorrect because it is the direct labor cost.

Option B is incorrect because it is the sum of direct material cost and direct labor cost plus manufacturing overhead.

Option D is incorrect because it is the sum of direct material cost, direct labor cost, and manufacturing overhead plus selling and administrative expenses.