Use your calculator and a table of values to find the exact value of limit as x goes to infinity of the product of x and the sine of 1 over x. (the limit as x approaches infinity)

Check the picture below.

to do it using a spreadsheet, so... you simply enter a formula on the "y" column, in this case I used = sin(1/A1)  <---- notice A1 is relative addressing.

from there, you can just drag the little black square on the cell, the cell handle and drag it as far as you want, it'll copy the formula as you go.

Draw a right angled triangle with 50 being on the left and 9 being on base. use pythag to find hypotenuse. then use the sin rule and sub your numbers in.
1/50.8*9 = 0.177
so C