The answer would be B, hope this helped!
The Ghost of Christmas Present is referring to the approximately 1800 Christmases that have come and gone since the birth of Christ, culminating up to the point where the story is told.
<span>The sentence that does not contain any errors is D. Whose muddy shoes are these on my clean kitchen floor? This is because the possessive pronoun whose is correctly used here. In A, it should be Greg's, and not Gregs'. In B, it should be actresses' families, and not actresses families'. In C, it should be it's, because that means it is, and not its, which is a possessive pronoun (the dog wagged its tail).</span>
C. to discover if the dangers of genetic enhancements can be prevented
