Final answer:
The sentence that should be deleted from this procedural text is Option 2 because it introduces a subjective opinion into what should be an objective and fact-driven procedure.
Step-by-step explanation:
The sentence that should be deleted from this procedural text is Option 2: 'In a separate cup, mix the vinegar and food coloring. Obviously, red would be the best choice for lava, but use any color you wish.' While the information may seem relevant, it introduces a subjective opinion ('Obviously, red would be the best choice for lava') into a procedure that is supposed to be objective and fact driven. Option 1 and Option 3 provide necessary steps without introducing personal bias.
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