One of the fundamental questions in physics is the matter-antimatter asymmetry of the Universe, explored through charge-parity violation searches in neutrino oscillation experiments. Next-generation oscillation experiments like DUNE need to constrain the systematic uncertainties arising from our understanding of (anti)neutrino-nucleus scattering to within a few percent to achieve their physics goals. MINERvA, a dedicated (anti)neutrino-nucleus scattering experiment, plays a crucial role in constraining these uncertainties. This thesis presents MINERvA's first high-statistics direct measurement of nuclear dependence in charged-current inclusive antineutrino scattering on carbon, hydrocarbon, iron, and lead as a function of antimuon transverse momentum, p_T, and Bjorken x.

The analysis utilises interactions with a mean antineutrino energy of approximately 6 GeV, with reconstructed antimuons having a scattering angle of less than 17° relative to the antineutrino beam and an antimuon energy of 2-20 GeV. The measured per-nucleon differential cross-sections are reported with a precision of 7-9%, while the cross-section ratios of carbon, iron, and lead to hydrocarbon have uncertainties of 5% or less. The cross-sections for iron and lead indicate strong suppression at low p_T and Bjorken x, and an enhancement at high p_T. These effects are observed to be more pronounced with the increasing size of the target nucleus and are not reproduced by the underlying simulation prediction. Comparisons to alternative models used in current (anti)neutrino interaction generators show some improvements in modelling over the base prediction model, yet they are still unable to fully reproduce the observed nuclear dependence in this analysis.

Importantly, the analysis provides a direct test of nuclear effects in inclusive antineutrino scattering, with major contributions from resonant pion production, deep inelastic scattering, and the transition region between these channels, which will be significant in DUNE. This measurement also represents one of the largest antineutrino datasets in this energy regime analysed to date.