Answer: Option (B) is the correct answer.
Step-by-step explanation:
Metalloids are the substance which show properties of both metals and non-metals.
Some properties of metals are that they are good conductor of heat and electricity, have shiny surface, have high melting point etc.
Some properties of non-metals are that they are bad conductor of heat and electricity, they are brittle and dull, have low melting point etc.
Thus, we can conclude that an unknown substance is tested and found to have the given physical properties represents a metalloid.