Answer:
C.
![-(5)/(12)\cdot ((6)/(5)\cdot ((1)/(3))\cdot (9)/(2)=(-(5)/(12)\cdot (6)/(5))\cdot (1)/(3)\cdot (9)/(2))](https://img.qammunity.org/2019/formulas/mathematics/middle-school/o8wo01xmc63b38y9ty2enu4pxjm01y7na7.png)
Explanation:
We have to find the equation in which associative property of multiplication is used.
Associative property of multiplication:
If a, b and c are number
Then,
![a\cdot (b.c)=(a\cdot b)\cdot c](https://img.qammunity.org/2019/formulas/mathematics/middle-school/h12tfscie3aljyroatdufu5eceecu8s6nd.png)
A.
![((-7)/(8)\cdot (2)/(5))+((-7)/(8)\cdot (3)/(5))=-(7)/(8)\cdot ((2)/(5)+(3)/(5))](https://img.qammunity.org/2019/formulas/mathematics/middle-school/2mrqektqozncbkbku5g8myp05ah6fmled3.png)
It is false because distributive property is used not associative property of multiplication.
B.
![((-1)/(4)-(5)/(3))-(3)/(5)=-(1)/(4)-((5)/(3)-(3)/(5))](https://img.qammunity.org/2019/formulas/mathematics/middle-school/4t0dlvzi4648q2x03se42ziqhlqqup47m6.png)
It is false because associative property of multiplication is not used.
In option C
![-(5)/(12)\cdot ((6)/(5)\cdot (1)/(3))\cdot (9)/(2)=(-(5)/(12)\cdot (6)/(5))\cdot ((1)/(3)\cdot (9)/(2))](https://img.qammunity.org/2019/formulas/mathematics/middle-school/i7ollb9e3qbnja7e5wf6gfmzl7z1hhfoja.png)
It is true because associative property of multiplication is used.
In option D
![(-6)/(7)\cdot (8)/(11)\cdot (1)/(3)=(8)/(11)\cdot (-6)/(7)\cdot (1)/(3)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/pidcudi16uokljeilvd37z9fwytqk2j02q.png)
It is not true because commutative property of multiplication is used not associative.