Maximum temperature that can be attained in box type solar cooker is:
A. $20^\circ C\;{\text{to 5}}0^\circ C\;$
B. $10^\circ C\;{\text{to 2}}0^\circ C\;$
C. $100^\circ C\;{\text{to 14}}0^\circ C\;$
D. $300^\circ C\;{\text{to 35}}0^\circ C\;$

Hint: The devices which use the sunlight as the source of heat to cook food are known as the solar cookers. They do not use any fuel to be operated. The devices are left in the open surroundings where the sunlight can fall on it easily.

Complete answer:
Remember the simple most solar cooker can reach the temperature just above the highest temperature of the thermometer. Cookware should be dark coloured to absorb the concentrated solar energy released from the sun’s rays.
Since, most of the solar cookers can attain the maximum temperature from about \[85^\circ C\;{\text{to 15}}0^\circ C\;\]. With this temperature solar cooker can sterilize water or can prepare most foods which can be made in a conventional oven or an ordinary stove which can prepare food such as bread, vegetables and meat over the period of hours without using any fuel.

So, the correct answer is “Option C”.

Additional Information:
In comparison to the box type solar cooker, the parabolic solar cooker attains the highest temperature.

Note:
The proper dimensions in the box type of the solar cooker are the most important to reach the required temperature. Generally the biggest problem in the solar cooker resulting in the very bad manner is due to the lack of good insulation in the cooker and not sealing all the holes or the gaps in the box. The proper reflectors should be made.