a light-year is an appropriate unit for measuring the time it takes to travel to the sun the time it takes to travel to mars the distance between galaxies the distance between earth and the moon

the wetland preservation movement began in the u.s. in earnest with the clean water act (cwa) of 1972. although not specifically written to protect wetlands, the cwa is comprised of a series of regulations designed to prevent pollutants from contaminating u.s. waters.

the correct answer is option d.

an appositive is a noun, noun phrase or noun clause which follows another noun or noun phrase in order to describe it or name it another way. they are usually used between commas, brackets or dashes.

the example sentence with the correct use of commas is the following:

her uncle, the man over there in the red shirt, owns the hardware store in town.

la transducción de señal ocurre cuando una molécula de señalización de fluido extracelular activa un receptor de superficie de la célula.