Answer:
A) positive externalities
Explanation:
Positive Externalities represents a level of benefit that external or third parties can enjoy as a result of a a research or an economic transaction. It is the benefits that competitors in a business line for instance, can enjoy as a result of the technological breakthrough in product or process by a business.
In other words, as in the question, while Bell Laboratories developed the laser technology, competitors and other businesses have been able to incorporate the developed technology in various applications including data transmission, medical use among others.
Therefore, although they didn't develop the technology, they benefit from its development