What types of reactions are catalyzed by enzymes? A. Hydrolysis
B. Dehydration Synthesis (also known as Condensation)
C. All of these
D. Other types of reactions​

is B. Dehydration synthesis

Explanation:

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The correct answer is b. an operational definition.  

Explanation:

An operational definition constitutes the set of procedures that describe the activities that an observer must carry out to receive sensory impressions, which indicate the existence of a theoretical concept to a greater or lesser degree. In this sense, it tries to clearly indicate how the variables are going to be manipulated or measured and also indicates that to measure a variable, it is necessary to carry out a series of activities or procedures. It is the one that builds or adapts from others, based on the observable characteristics of the phenomenon; indicating the concrete, empirical elements or indicators of the fact to be investigated.