Concept:
A hoarding is a large public advertising display placed outdoors to attract public attention. Hoardings are commonly installed:
• Along roads
• On highways
• On building walls
• In crowded public spaces
Hoardings belong to outdoor advertising media and are often considered billboard or signboard advertisements.
The question asks which category hoardings do not belong to.
Step 1: Understanding hoarding advertisements.
Hoardings are designed for:
• Mass public visibility
• Outdoor audience exposure
• Large-scale advertising
They are generally installed in open public locations.
Step 2: Analyzing Option (A) Outdoor advertisement.
Hoardings are a major form of outdoor advertising because they are displayed outdoors for public viewing.
Hence, Option (A) is incorrect.
Step 3: Analyzing Option (B) Bill board advertisement.
Billboards and hoardings are closely related forms of large outdoor advertising structures.
Hence, Option (B) is incorrect.
Step 4: Analyzing Option (C) Indoor advertisement.
Indoor advertisements are displayed inside buildings such as:
• Shopping malls
• Airports
• Theaters
• Offices
Since hoardings are primarily outdoor structures, they are not indoor advertisements.
Therefore, this option is correct.
Step 5: Analyzing Option (D) Sign board advertisement.
Hoardings can function as large signboard advertisements for branding and public communication.
Hence, Option (D) is incorrect.
Final Conclusion:
Hoarding is not a type of:
\[
\boxed{\text{Indoor advertisement}}
\]
Therefore, the correct option is:
\[
\boxed{(3)}
\]