Error Spotting – Choose the part (A–D) that contains a grammatical error, or choose No error if the sentence is fully correct. Sentence (parts correspond to options below): A) The chairman welcomed B) all the guests and C) gave an outline of the D) activities performing by the Company.

Introduction / Context:
The question tests correct participle use and passive constructions in noun phrases. English often needs a past participle or a reduced relative clause to modify a noun when the meaning is passive or completed.

Given Data / Assumptions:

• Noun being modified: activities
• Participle used: performing
• Agentive by-phrase: by the Company

Concept / Approach:
When a noun is modified by a phrase indicating that something is done to it or that it is carried out by an agent, we typically use a past participle performed or a reduced relative clause being performed. The active participle performing is ungrammatical in this passive sense.

Step-by-Step Solution:

Verification / Alternative check:
Test with a relative clause: activities that are performed by the Company. Reduction to activities performed by the Company validates the correction.

Why Other Options Are Wrong:

• A) Correct simple past verb welcomed.
• B) Coordinating phrase is fine.
• C) Prepositional phrase is idiomatic.

Common Pitfalls:
Writers often choose -ing forms by default. Ensure that the participle matches the intended voice and time reference. Use performed for passive, ongoing completed activities.

Final Answer:
Option D contains the error. Use activities performed by the Company.