Answer:
<u><em>The answer is</em></u>: <u>B. boiling.</u>
Explanation:
<em>The value of the melting and boiling points are affected by the value of the atmospheric pressure.
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<em>The Celsius degree is the unit corresponding to the melting and boiling temperatures of water at 1 atm pressure</em>. Celsius: Melting 0 ℃, Boil 100 ℃.
<em>When a food is</em> frozen <em>at normal atmospheric pressure, its</em> temperature drops to 0 ° C, <em>at which time the water begins to turn into ice.
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<em>Normally, the atmospheric pressure that exists at sea level is taken as a reference.</em> There it takes a value of 1 atmosphere.
Therefore, although the pressure is 1 atmosphere for all processes, the one that needs more temperature is the Boiling, which is 100 ° C.
<em><u>The answer is</u></em>: <u>B. boiling.</u>