ce sont v. elles sont

Question

In the sentence: À qui sont ces balles ? ________ les miennes. Why can't I say 'ce sont les miennes'?

Answer

Hi Richard,
In this example, you can say -
... ce sont les miennes 
as well as
... elles sont les miennes 
 Where is that sentence from?

Answer

It was from a test and was marked incorrect with 'ce sont'. Strange, as it seems to be correct.

Answer

Bonjour Madame Cécile !In one of your replies to a query, you mentioned the following tip ->In French, we cannot say -1.Elle/il est +une/un/ la/le /du/mon/ma /sa/son/leur  or a name2.Ils/Elles sont +les/des/mes/leursso it has to be - C'est or Ce sont So, Madame, why is the alternative- “Elles sont les miennes” correct ? As, it has to be ‘Ce sont + les miennes’. Also, “les miennes” is a possessive pronoun which replaces a previously used noun, so the use of “Elles” in the beginning will also not be correct.Being a learner, I may be wrong, so I would appreciate your opinion.Bonne journée!

Answer

Hi Richard, 
As this is from a quiz, could you repost your query via the Report it button on your correction board as it will link directly to the quiz in question and it can be addressed more easily in full context?
Shrey, this rule on thumb sometimes falls short and you will find a few instances when il est/ c'est is debatable.
In this example, and having checked with several native speakers, this is one of them.
Bonne Continuation!