this 17-year-old son vs his 17-year-old son

[Peter3791]

English Language Proficiency Tests, Advanced Level

ESL/EFL Test #761 "Money: Buying and Spending (3)", question 9

"If you decide to go to college, you can live here for free. However, if you don't, I will ask you to pay $250 in ......... per month," James said to this 17-year-old son.

(a) loan
(b) price
(c) purchase
(d) rent

English Language Proficiency Tests, Advanced Level

ESL/EFL Test #761 "Money: Buying and Spending (3)", answer 9

"If you decide to go to college, you can live here for free. However, if you don't, I will ask you to pay $250 in rent per month," James said to this 17-year-old son.

Correct answer: (d) rent

Your answer was: correct
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James said to this 17-year-old son.

Please correct the typo. Or did I get it wrong and James has this 17-year-old son and that one, too?

[Linda]

No, you're right. It should be 'his' son.
We'll correct that right away.
_________________
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