20.
The answer is: B
Explanation
The correct option is B: English.
According to Section 9 of the Industrial Employment (Standing Orders) Act, 1946, the text of the certified standing orders shall be prominently posted by the employer in English and in the language understood by the majority of his workmen on special boards to be maintained for the purpose at or near the entrance through which the workmen enter the industrial establishment and in all departments thereof where the workmen are employed. This is to ensure that the workmen are aware of the terms and conditions of their employment and their rights and obligations under the certified standing orders.