This sentence talks about an idea that came into being more than ten years ago. The structure "the idea of... fund (B) over a decade ago" clearly calls for a verb in the past tense that means the idea came into existence or began at that time.
Option (a): Grammatically, "emerged" is the past tense of a verb, so it fits the sentence structure. Contextually, it is appropriate. "Emerged" means something appeared or came into being, which fits well with an idea developing or surfacing over a decade ago. This is a suitable fit both grammatically and contextually.
Option (b): Grammatically, "collect" is in the base form and does not match the past-tense requirement indicated by "over a decade ago." Contextually, "collect" refers to gathering things, not to an idea being conceived or introduced. It does not work here.
Option (c): Grammatically, "affords" is in the present tense and does not fit the past-time marker "over a decade ago." Contextually, "affords" means "provides" or "gives," which does not make sense when describing how an idea began.
Option (d): Grammatically, this is also the base form and does not align with the past time reference. Contextually, "prepare" means to get ready, not to originate or surface. It does not fit here.
Option (e): Grammatically, "claimed" is in the correct past tense. Contextually, however, it refers to asserting something as true or making a declaration, which doesn't align with an idea being formed or beginning. It does not convey the right meaning.
Hence, option (a) is the answer.