In an appropriately designed experiment, a scientist is able to test the effect of:
a) a single variable
b) multiple variables
c) the hypothesis
d) scientific observations

In an appropriately designed experiment, a scientist is able to test the effect of A. a single variable.

In an experiment that's appropriately designed, there is typically one independent variable. The independent variable is the variable that one manipulates in an experiment.

In an appropriately designed experiment, a scientist is able to test the effect of a single variable. This allows the scientist to determine if the variable that is manipulated has an impact on the subject.

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A) a single variable

Explanation:

An appropriately designed experiment usually involves only one independent variable. This allows the scientist to truly determine whether the variable manipulated is what had an effect on the subject. You may test more than one variable, but this is usually done or experimented separately, or one at a time.

The correct answer is - D. continuous replication.

Explanation:

Okazaki fragments are short DNA sequences synthesized in the lagging strand as DNA polymerase enzyme is able to synthesize only from 5' to 3' so nucleotide can not bind on 5' end but only 3' end and the DNA strands are antiparallel.

They are short fragments of DNA synthesized from RNA primers on the lagging strand and combined by the ligase enzyme. Okazaki fragments show a discontinuous manner in the synthesis of DNA.