; and (2) may be extended, for a 2-year period, subject to approval by the Secretary, and based on the State’s progress in— (A) increasing the number and percentage of children from low-income families in each age group of infants, toddlers, and preschoolers, enrolled in high-quality State early learning programs; (B) increasing the number of high-quality State early learning programs in low-income communities; and (C) incorporating the program quality findings and recommendations, as appropriate. (c) State uses of funds (1) In general A State receiving a grant under section 3(b) shall use the grant funds to undertake activities to develop the components of early learning services described in section 4(c)(4) that will allow the State to become eligible and competitive for a grant described in section 3(a). (2) Priority In improving the quality of State early learning programs in the State, the State shall prioritize the quality of State early learning programs serving children from low-income families. 6. Research and evaluation From funds reserved under section 3(c)(1)(B), the Secretary and the Secretary of Health and Human Services, acting jointly and in accordance with section 11, shall carry out activities to ensure the success of grants to States under this Act. 7. Benchmarks; indicators; reporting (a) Indicators The Secretary shall define, by regulation, indicators to be used to measure success on the activities carried out under a grant under this Act, the primary indicator of which shall be increasing the number and percentage of low-income children in high-quality, State early learning programs. (b) Benchmarks Each State receiving a grant under this Act shall— (1) develop quantifiable benchmarks for the State and the activities supported under the grant based on the indicators described in subsection (a) that are applicable to the State; (2) submit the benchmarks for approval to the Secretary