Which of the following is true of the rights of an employee?
a. for the rights of an employee to exist, they must be spelled out at the time of appointment.
b. for the rights of an employee to exist, they must be contained in a formal employment contract that the employee has signed.
c. an employee’s contractual rights are based on a specific contract with an employer.
d. moral rights of the employees are typically the result of specific laws or statutes passed by federal, state, or local governments.

For the rights of an employee to exist, they must be contained in a formal employment contract that the employee has signed.

Option B

Explanation:

When the employee is appointed in a particular company for a post, the employer makes a contract signed by the employee. In that contract all the terms and the conditions are given on which the employee and the employer have agreed upon.

This contract gives the rights  of the employee also that he will enjoy while working and being in a written form, the rights of the employee are always secure. This gives the job security to the employee through that contract.

the correct answer is the following is a list of inventions made in the medieval islamic world, especially during the "islamic golden age" (8th to 13th centuries),[1][2] as well as the late medieval period, especially in the emirate of granada and the ottoman empire.

science and technology in the islamic world adopted and preserved knowledge and technologies from contemporary and earlier civilizations, including persia, india, china, and greece-roman antiquity, while making a number of improvements and innovations.