# Spontaneous combustion is a phenomenon in which _____ ? with Answer - Mechanical Engineering Mcqs | TestPrep

> Solved MCQ: Spontaneous combustion is a phenomenon in which _____ ? Correct Answer: C. coal bursts into flame without any external ignition source but by itself due to gradual increase in temperature as a result of heat released by combination of oxygen with coal. Verified answer explanation for FPSC, PPSC, MDCAT, NTS, and CSS competitive exam preparation.

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# Spontaneous combustion is a phenomenon in which _____ ?

Direct Answer & Quick Reference

The correct option is **C. coal bursts into flame without any external ignition source but by itself due to gradual increase in temperature as a result of heat released by combination of oxygen with coal**.

A. all the fuel burns instantaneously producing high energy release

B. fuel burns with less air

C. coal bursts into flame without any external ignition source but by itself due to gradual increase in temperature as a result of heat released by combination of oxygen with coal **(Correct Answer)**

D. explosion in furnace

E. none of the above

✨ Explain with AI

Verified Key: C. coal bursts into flame without any external ignition source but by itself due to gradual increase in temperature as a result of heat released by combination of oxygen with coal
Solved by 1,610+ students

Verified against official examination board answer keys and standard curriculum textbooks.

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