The following table gives the QR company data for seven $(7)$ years; from $2015$ to $2021.$

Actual

The forecast for $2018$ to $2021$ using a $3-$period Simple Moving Average forecasting method is:

a$.27\mathrm{.}33,27\mathrm{.}67,26,25$

b$.27,28,26,30$

c$.30,27,28,27$

d$.27\mathrm{.}33,27\mathrm{.}67,27\mathrm{.}33,30$