A solid aluminium ball, when quenched in a water bath maintained at 40°C, cools down from 550°C to 450°C in 20 seconds. The expected temperature of the ball after next 20 seconds may be about __________ °C.

A. 370

B. 340

C. 320

D. 300

Please do not use chat terms. Example: avoid using "grt" instead of "great".

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