Question

researcher lin zhi developed a process for increasing the tensile strength --measured in gigapascals, or gpa--of silkworm ______ dissolving and reweaving the silk in a solution of iron metal ions, zinc, and sugar, zhi increased the amount of force required to stretch it from approximately 0.5 gpa to 2 gpa. which choice completes the text so that it conforms to the conventions of standard english? choose 1 answer: a silk and by b silk by c silk, by d silk. by

Explanation:

To determine the correct answer, we analyze the sentence structure. The phrase "increasing the tensile strength... of silkworm silk" is followed by the method of doing so, which is introduced by "by dissolving...". Option A adds an unnecessary "and", making the structure awkward. Option C uses a comma, which would create a non - standard pause. Option D uses a period, which would make the second part a separate sentence, but it should be a part of the same sentence explaining the method. Option B ("silk by") correctly connects the noun "silk" with the method introduced by "by" without any incorrect punctuation or conjunctions.

Answer:

B. silk by