The use of the word "simultaneous" actually describes the verb "developed," even though it is next to the verb "researchers." The issue can be corrected by making the word "simultaneous" an adverb. "By two researchers simultaneously" is the correct answer choice.

The use of the adverb "horribly" is wrong, as the word modifies a noun, "comedian," and should actually be an adjective. This problem can be corrected by shifting "horribly" to its adjectival form. Therefore, the correct answer choice is "He was a horrible comedian, with no ability to make anybody laugh."

The use of the adjective "perfect" is incorrect in this sentence, as it modifies the verb "handled." A verb can only be modified by an adverb, meaning "perfect" must be changed to its adverbial form. As the only answer choice to use the adverb "perfectly" instead of the adjective "perfect," the correct answer choice is "as it always handled its money perfectly."

The use of the adverb "thoughtfully" is incorrect here, as it is being used to modify the noun "consideration." Adjectives, not adverbs, are used to modify nouns. The correct phrase is therefore "giving it thoughtful consideration," which uses the adjective "thoughtful" instead of the adverb "thoughtfully."

The word "alleged" is modifying the word "made," a verb, which needs an adverb to modify it. The adverb form of "alleged" is "allegedly," which makes the correct answer "allegedly made."

The example sentence incorrectly uses an adjective where an adverb is needed. "Bitter", in this context, modifies the verb "was," and therefore should be replaced by the adverb "bitterly." If the cold were being used as a noun, then the adjective form of "bitter" would be appropriate—for example, "We were wrapped in a bitter cold." The correct version of the example reads, "We had a terrible time at the football game. It was bitterly cold."

The use of the word "usual" in the sentence is incorrect, as it describes the verb "took," which means it needs to take an adverb form. The only answer choice with the correct form that also keeps the intended meaning of the sentence is "The old man usually took."

The word "increasing" in the sentence is used to describe the verb phrase "being delayed." Even though these words are not the verb in the sentence, they still need an adverb form to describe them. The correct answer is "Marriages are increasingly being delayed."

This sentence contains a misuse of an adverb. The word "quickly" is meant to describe the noun "response," but adverbs cannot describe nouns. What is needed here is the adjective form of the word, which is "quick." The proper choice is, "Ahmed was known for his quick." 

The word "fast" is supposed to modify the word "built." Adverbs modify verbs, but "fast" is an adjective. The correct choice is "quickly" (fastly is not a word). While "with speed," is technically also correct, it adds another word, which makes it less concise. The correct choice is, "Jenny built programs quickly."