Company: NMZ
Filing Date: 2025-11-18
Form Type: N-14 8C/A
Source: 0001999371-25-018025
Chunk: 305

Company: NUVEEN MUNICIPAL HIGH INCOME OPPORTUNITY FUND
Filing Date: 2025-11-18
Form: N-14 8C/A
Chunk 305
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 affected by foreseeable     
 events.                                                                                   |

| AA | Very                                                                                         
 high credit quality. ‘AA’ ratings denote expectations of a very low default                  
 risk. They indicate very strong capacity for payment of financial commitments. This capacity 
 is not significantly vulnerable to foreseeable events.                                       |

| A | High                                                                                    
 credit quality. ‘A’ ratings denote expectations of low default risk. The                
 capacity for payment of financial commitments is considered strong. This capacity may,  
 nevertheless, be more vulnerable to adverse business or economic conditions than is the 
 case for higher ratings.                                                                |

| BBB | Good                                                                                         
 credit quality. ‘BBB’ ratings indicate that expectations of default risk                     
 are currently low. The capacity for payment of financial commitments is considered adequate, 
 but adverse business or economic conditions are more likely to impair this capacity.         |

| BB | Speculative.                                                                                   
 ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly                  
 in the event of adverse changes in business or economic conditions over time; however,         
 business or financial flexibility exists that supports the servicing of financial commitments. |

<div align='center'>A-5</div>

| B | Highly                                                                                 
 speculative. ‘B’ ratings indicate that material default risk is present,               
 but a limited margin of safety remains. Financial commitments are currently being met; 
 however, capacity for continued payment is vulnerable to deterioration in the business 
 and economic environment.                                                              |

| CCC | Substantial                                                             
 credit risk. Very low margin for safety. Default is a real possibility. |

| CC | Very                                                               
 high levels of credit risk. Default of some kind appears probable. |

| C | Near                                                                                   
 Default. A Default or default-like process has begun, or for a closed funding vehicle, 
 payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’      
 category rating for an issuer include:                                                 |

| a. | the                                                                                          
 issuer has entered into a grace or cure period following non-payment of a material financial 
 obligation;                                                                                  |

| b. | the                                                                                     
 formal announcement by the issuer or their agent of a distressed debt exchange (“DDE”); 
 and                                                                                     |

| c. | A                                                                                            
 closed financing vehicle where payment capacity is irrevocably impaired such that it         
 is not expected to pay interest and/or principal in full during the life of the transaction, 
 but where no payment default is imminent.                                                    |

| RD | Restricted                                                                                    
 default. ‘RD’ ratings indicate an issuer that