GENERAL KNOWLEDGE

Detailed explanation-1: -The SI base units are the standard units of measurement defined by the International System of Units (SI) for the seven base quantities of what is now known as the International System of Quantities: they are notably a basic set from which all other SI units can be derived.

Detailed explanation-2: -A base unit (also referred to as a fundamental unit) is a unit adopted for measurement of a base quantity.

Detailed explanation-3: -noun. : one of a set of fundamental units in a system of measurement that is based on a natural phenomenon or established standard and from which other units may be derived. The base units of the International System of Units are the meter, kilogram, second, ampere, kelvin, mole, and candela.

Detailed explanation-4: -A fundamental unit is a measurement tool used for a base quantity. A fundamental quantity is any physical quantity that cannot be represented in terms of any other physical quantity in a traditionally defined subset of physical values.

Detailed explanation-5: -The foundation of modern metrology is the International System of Units (SI), which is used internationally to define the fundamental units of measurement. These are used to derive other units and are used to define other measurement units, such as may be used locally.