Capacitor having lowest capacitance has medium of dielectric : 

The correct answer is option 1 

Concept:

• The capacitor is the electrical component. it has two terminals. It is used to store energy as electrostatic energy
• Dielectrics are insulators. They will be placed between the capacitor's parallel plate
• Air capacitors have a small capacitance which mostly  lies between 100pF and 1nF
• The paper capacitor has a capacitance range of 0.001 to 2.000 microfarad
• Mica capacitor is available in a range of voltages from low to high. It has capacitance values ranging from 20 pF to 10 F
• Plastic capacitors are film capacitors. These capacitors made, generally use polypropylene film as the dielectric. Typical film capacitors have capacitances ranging from below 1nF to 30µF
• So option 1 is right