When the price of tortilla chips rose by $10$ percent, the quantity of tortilla chips sold fell $4$ percent, and the sale of dips $($like salsa and bean dip$)$ fell $8$ percent. This set of facts indicates that the cross$-$price elasticity between tortilla chips and dips is so the two are

a$.0\mathrm{.}8$; substitutes

b$.-0\mathrm{.}4$ ; complements

C$.-0\mathrm{.}8$; complements

d$.0\mathrm{.}4$; substitutes