?Lead pencil? contains [DPMT 2001; IIT 1990]

1.	?Lead pencil? contains [DPMT 2001; IIT 1990]
A.	\[PbS\]
B.	Graphite
C.	\[({{H}_{3}}B{{O}_{3}})\]
D.	\[Pb\]
Answer» C. \[({{H}_{3}}B{{O}_{3}})\]

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?Lead pencil? contains [DPMT 2001; IIT 1990]

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