Each sentence has two blanks. Choose the pair that fits best. Despite repeated policy interventions, the informal sector continues to ________ as the principal source of employment, largely because reforms have failed to ________ its structural constraints.

“Function as” is idiomatic; “address structural constraints” fits contextually. adapt — to adjust or change to suit new conditions promote — to support, encourage, or help something grow or succeed emerge — to come out, to appear, to become visible conceal — to hide something or keep it secret weaken — to make something less strong or less effective dissolve — to break apart, melt, or cause something to disappear decline — to decrease, weaken, or worsen over time; also to politely refuse challenge — to question, oppose, or test something function — to work or operate in a particular way address — to deal with or focus on a problem or issue