Which of the following substances is considered an electrolyte?

• A. NaCl (sodium chloride) dissolved in water
• B. C_6H_{12}O_6 (glucose) dissolved in water
• C. CH_3OH (methanol) dissolved in water
• D. CCl_4 (carbon tetrachloride) in liquid form

Answer: (A)

Verified step by step guidance

1. Understand that an electrolyte is a substance that, when dissolved in water, produces ions and thus conducts electricity.
2. Recognize that ionic compounds like NaCl dissociate into their constituent ions (Na\^{+} and Cl\^{-}) in water, making the solution conductive.
3. Note that molecular compounds such as C_6H_{12}O_6 (glucose) and CH_3OH (methanol) dissolve in water but do not dissociate into ions; they remain as neutral molecules and do not conduct electricity well.
4. Identify that CCl_4 (carbon tetrachloride) is a nonpolar molecular compound and is not soluble in water; it also does not produce ions.
5. Conclude that among the given substances, only NaCl dissolved in water acts as an electrolyte because it produces free ions that conduct electricity.