Directions (9-13): In each of the following questions one sentence has been given. Each sentence has two blanks. From the options given below the sentence, pick the pair of words that fits into both the blanks respectively to make the sentence contextually meaningful and mark the letter corresponding to it as your answer.

Part of Justin’s hyperactivity _________________ that he couldn’t concentrate __________________ to read.

The correct answer is meant, enough.

Let's analyze the sentence structure and context step-by-step to understand why this pair of words fits correctly into the blanks:

1. First Blank Analysis:
The subject of the sentence is "Part of Justin's hyperactivity". We need a verb in the past tense that links the condition (his hyperactivity) to its result/consequence described in the clause beginning with "that...".
- "Meant" (past tense of mean) fits logically, indicating that his hyperactivity had the consequence or result that he couldn't concentrate.
- Options like "summarise" (present tense verb, grammatically incorrect) or "concluded" / "implied" do not naturally express the cause-and-effect relation of a physical/mental trait leading to a practical limitation.

2. Second Blank Analysis:
The phrase "couldn't concentrate ______________ to read" requires an adverb that modifies the verb "concentrate" and completes the degree structure "enough + to-infinitive" (concentrate enough to read).
- "Enough" correctly completes this idiomatic structure, indicating the sufficient level or degree of concentration required for reading.
- Words like "ended", "just", or "by" do not complete this grammatical or logical structure appropriately.

Combining both words, the complete, contextually meaningful sentence is:
"Part of Justin’s hyperactivity meant that he couldn’t concentrate enough to read."