Why is there no rock record of the hadean period?

a. rocks only formed near subduction zones during this period.
b. the lack of ozone prevented rock formation.
c. earth's temperature was too high for solid rocks to form.
d. only metamorphic rocks formed during that period.

Option C,  Earth's temperature was too high for solid rocks to form.

Explanation:

During the Hadeon age ( some 4.6 billion years ago), the earth was at its initial stage of formation. By that time the temperature of earth was extremely high and extraterrestrial bombardments from  other planets or celestial structures further raised the earth’s temperature. Due to such extremities and high temperature the rocks at the surface of earth could not solidify and hence no traces of rocks can be found from the Hadeon era.  

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