The correct answer is: B. An indifference curve relating the two goods will be linear.
An indifference curve is a graph that shows all the combinations of goods that a consumer is indifferent between. If two goods are perfect substitutes, then the consumer is indifferent between any two combinations of the goods that have the same amount of one good and the same amount of the other good. This means that the indifference curve will be a straight line, because the consumer is willing to trade one good for the other at a constant rate.
Option A is incorrect because indifference curves for perfect substitutes are linear, not curvilinear.
Option C is incorrect because indifference curves for perfect substitutes are not divided into two segments.
Option D is incorrect because indifference curves for perfect substitutes are not convex to the origin.