<h3>Answer:</h3>
Option-B (Halide; oxide) is the correct answer.
<h3>Explanation:</h3>
<em> Halides</em> are those substances which contains negatively charged halide ion i.e. X⁻.
Examples: F⁻ (Fluoride) , Cl⁻ (Chloride) , Br⁻ (Bromide) , I⁻ (Iodide) e.t.c.
<em>Oxides </em>are those substances which atleast containn one Oxygen atom.
Examples: FeO (Iron Oxide), Cr₂O₃ (Chromium Oxide)
<em>Silicates</em> are those anionic substances which contains silicon and oxygen with general formula [SiO. 4−x] n.
Examples: [SiO₄]⁻⁴ (Nasosilicate) , [Si₂O₇]⁻⁶ (Sorosilicates)
<em>Carbonates </em>are those substances which contains carbonate anion i.e. CO₃²⁻.
Examples: Na₂CO₃ (Sodium Carbonate) , MgCO₃ (Magnesium Carbonate)
<h3>Conclusion:</h3>
As in NaCaAlF, F⁻ is present hence, it is an Halide and the presence of O in FeCrO makes it Oxide.
