New regulations require costly new pollution control equipment.
Resultant price increases for Risemian manufactured goods will lead to the loss of some export markets.

Conclusion: Clearly, therefore, annual exports of Risemian manufactured goods will in the future occur at diminished levels.

The conclusion says that annual exports of Risemian manufactured goods will diminish. Note that we are not talking only about the currently manufactured goods but about all Risemian manufactured goods - those that are manufactured currently and those that will be manufactured in the future too.

We need to weaken this.

(A) The need to comply with the new regulations will stimulate the development within Risemia of new pollution control equipment for which a strong worldwide demand is likely to emerge.

Due to this need, Risemia will develop new equipment. This equipment will have strong worldwide demand. So the equipment that will be made in Risemia will have strong demand outside. Hence, the exports may not fall. These new products may carry the export numbers in the future. Correct. There is no reason to believe that equipment developed in Risemia for use in Risemia may not be manufactured in Risemia. It is a fair assumption that developed in Risemia means designed and manufactured there.

(E) The stockholders of most of Risemia's manufacturing corporations exert substantial pressure on the corporations to comply with environmental laws.

Doesn't talk about exports at all. What stockholders feel is irrelevant.

Answer: A