Final answer:
The sign of q would be negative because heat is lost by the system, and the sign of w would be positive because work is done by the surroundings, making the answer D. -q and +w.
Step-by-step explanation:
If heat is lost by the system and work is done by the surroundings, the sign of q (heat) would be negative and the sign of w (work) would be positive. According to the conventions in chemistry, with the system losing heat, q would have a negative sign because energy is transferred away from the system. When work is done by the surroundings on the system, it results in energy being transferred to the system, hence w is positive. Therefore, the correct answer is D. -q and +w. With regard to the statements provided, the First Law of Thermodynamics states that the change in the internal energy of a system is represented as ΔU = q + w, reiterating the conventions regarding the signs of q and w. Heat flow and work have negative signs when energy moves from a system to the surroundings, and positive signs when energy moves into a system from the surroundings.