Logical question for MS and PhD entry exam

Laminin 332 is an essential component of the dermal-epidermal junction, a highly specialized basement membrane zone that attaches the epidermis to the dermis and thereby provides skin integrity and resistance to external mechanical forces. If you were saying this outloud you would use inflection in your voice to draw the distinction. Because you can’t put that emphasis in your writing, you should be careful about where you place your “only”! If you say “Laminin 332 is only secreted by mature corneal epithelial cells.” The emphasis is placed on the “secreted” therefore this sentence says that mature cells only secrete the laminin, they don’t synthesize, remodel, transport or do anythign else with it. In contrast, when you say “laminin 332 is secreted only by mature corneal epithelial cells.” then emphasis is placed on the mature corneal epithelial cells. It says that immature cells don’t secrete laminins. Problem: Let’s say that your data has revealed that laminin 332 gets made and secreted by mature cells but not by immature cells. Which of the following phrases captures these findings best? A) Laminin 332 is only secreted by mature corneal epithelial cells. B) Laminin 332 is secreted only by mature corneal epithelial cells.