Which of the following sentences is LEAST grammatically correct?

a . Although Maria is over fifty, she looks younger than her children.
b .  Although Maria is over fifty and looks younger than her children.
c .  Maria, who is over fifty, looks younger than her children.
d . Maria looks younger than her children although she is over fifty.

Which is the right answer? I think b

B is the least correct, yes.

yes B

I say A

Yes, A.

A run-on is TWO sentences jammed together without any punctuation or capitals. Which one fits that description?

Thank you all

I have this question too:

Which of the following sentences (correctly uses commas)?

a. As trade expanded across the Mediterranean world, Western Europeans were able to enjoy spices and other exotic products.

b.As trade expanded, across the Mediterranean world Western Europeans were able to enjoy spices and other exotic products.

c. As trade expanded across the Mediterranean world Western Europeans were able to enjoy spices, and other exotic products.

d. As trade expanded across the Mediterranean world Western Europeans, were able to enjoy spices, and other exotic products.

Thank you Tiger and Anonymous 2💚💚

Of the following sentences, which is a (run-on sentence)?
a. Carbon dioxide is, in turn, excreted by plants and it is produced by a variety of human activities, such as the burning of hydrocarbon fuels.

b. Along with carbon dioxide, water vapor and other waste products can accumulate in the atmosphere this creates a kind of barrier to the reflection of solar energy.

c . Some of the solar energy would otherwise bounce off the earth's surface and escape through the atmosphere.

d.  If enough carbon dioxide and other materials accumulate, scientists fear that our environment will become like a greenhouse.

b. is incomprehensible.

So the answer is C

Because B has a comma
Is it right?

Sorry … I should have phrased this better:

"A run-on is TWO sentences jammed together without any punctuation or capitals where the sentences come together. Which one fits that description?"

Not C.